Air compressor and valve



Nev.` 24, 1925.

Y BAKER AIR COMPRESSOR AND VALVE w 42, F A z 8. Z 5. J. Lm

Patented Nov. 24, 1925.,

UNITED sfrATEs PAT-leur` OFFICE.

DEXTER C. BAKER, 0F OAKLAND, CALIFORNIA, ASSIGNOR T0 BAKER-HANSEN MANU-FAC'.I."U'RI1\T 11l CO., OF ALAMEDA, CALIFORNIA, CORPORATION 0FCALIFORNIA.

am ooMrEEssoa'ANn VALVE.

Application filed May f8,

To all 'whom' it may concern:

Be it known that l, DEXTER C. BAKER, a citizen of the United States, anda resident of the city of Oakland, in the county of Alameda and State ofCalifornia, have invented a new and useful Air Compressor and Valve, ofwhich the following is a specilication.

rlhis invention relates to an air compressor, and more particularly tothe con-` trol of the air ports in a reciprocating type compressor.

In such compressors, itv is of course neoessary to permit air to enterthe compression cylinder on the intake stroke of the piston, and topermit the piston to discharge the compressed air on its compressionstroke. llt has been customary to provide various forms of valves whichseat by spring pressure and in which this pressure is tempovkrarilyovercome during the proper changes in the cycle of the compressor'.'llhus dur'- ing the intake or suction stroke, the intake valve springis overcome by the suction and permits entry of air to the cylinder.Upon a reversal of movement of thepiston, the pressure of the air withinthe cylinder closes this valve and serves to open the discharge valveleading to an air tank;

lin such constructions it has been found that much energy is used up inoperating the valves, and it is therefore one of the objects of myinventionto make it `possible to move the valve parts with little eort,while still insuring accurate seating` and proper operation., f

It is another object of my invention to improve in general the operationof reciprocating air compressors.

, llt is still another object of my invention to provide an intake valveconstruction. that ensures a large and quick opening upon the beginningof the suction stroke, and a rapid closure when the piston startstocompress the air drawn in.v lin this wa there is greater certainty thatno wirerawng of the vincolningvair can result, and theV compressor mayoperate mosty leciently and vutilize the cylinder volume to its greatestextent l t 'f p f lin order that the compressor operate mostsuccessfully, it is' advantageous to `rmit 1923. Serial No. 637,437.

the piston, inA its reciprocations, to travel substantially the fulllength of the cylinder, so that on compression substantially all of thecompressed air may he forced through the discharge valve. l accomplishthis highly desiraloleV result by arranging the valves in such a waythat they do not occupy any material space within the cylinder.

My invention possesses other advantageous features, some of which, withthe foregoing, will be set forth at length in the following description,Where I shall outline in full that form of the invention which Ihave'selected for illustration in the drawings accompanyingv and formingpart of the present specification. Although l have shown in the drawingsbut one embodiment of my invention, l do not desire to be limitedthereto, since the invention as set forth in the claims vmay be embodiedin other forms also. 1

Referring to the drawings: 1 Figure 1 is a sectional view showing theend of a compressor cylinder, in which valves embodying my invention areused;

Fig. 2 is a plan kview of the valve plate used in the compressorillustrated in Fig. l; Fig. 3 is a sectional view of the plate shown inFig..2;

Fig. 4c is a plan View of one form of member adapted to exert aresilient closing force for the intake valve shown in Fig. l;

Fig. 5 is a plan view of a member which is associated kwith the intakevalve;

Fig. 6 is a plan View of the intake valve, which is arranged to beseated by the memher illustrated in Fig. 4; and n Fig.. 7 is an enlargedsectional view through the intake valve illustrated [in Fi l. compressorcylinder 1l has a piston 12 which is arranged to be reciprocated thereinin any appropriate manner. Since the details of the cylinder, piston,and the source of mechanical power for reciprocating the piston form nopart of 'my present invention, it is considered unnecessary to describethese elementsfurther. llt is also evident that as man cylinders and asmany stages vmay be use 4in a complete air compressor as may he desired.rlhe cylinder head 13 in the present instance serves to provide an v y Avalve supporting plate 18may convenientlypbe utilized for supporting thevalve structure. This valve plate is interposed between the end ofcylinder 11 and the head 13, the three parts being securely fastenedtogether as by a plurality of screws 19 which extend through theseparts. This plate covers the cylinder end completely, except for a pairof sets eof annularly arranged apertures 20 and 2,1.. The set 20 servesto connect the cylinder with the annular intake passageway 14; wheneverthe f,

intake valve is opened. This valve may comprise a ring 22, shown ingreater detail in Fig. 6, which ring serves when it is seated,lto coverup all of the apertures 2O and prevent communication between thecylinder 11 and the passageway 14. This valve ring 22 is arranged in anannular groove 23 cut in the plate 1.8'on the side of the plate nearestthe cylinder 11.V Furthermore a second narrow groove 24 vis out in thebottom of the groove 23, which narrow groove con-I nects all of theapertures 20. The ring 22 is wide enough to cover up this narrow groove-as illustrated mostclearly inFig. 7.

In order that the lcompressor function properly, it is essential to keepthe ring 22 seated over the groove 24 until lthe suction or intakestroke begins. In order to ac-v complish this purpose in a highlysatisfactory manner and without taking up an appreciable amount of spacein the cylinder 11,

-I provide a very shallow spring cup 25,-

shown most clearly in Figs. 4 and 7. This cup is made of resilientmaterial, such as phosphor bronze, and its edge 26 is arranged tocontact with the ring 22 at or near its outer edge, on a surfacesubstantially coextensive with the series of intake apertures 20. Inorder to hold this spring'mernber 25 in proper operative position, abolt V27 passing through the cup and the plate 18 near their center maybe used. The. spring cup 25 takes up hardly any useful cylinder volume;atthe same time it ensures a substantially even pressure on the ring 22at ally points. This latter feature cannot be too strongly emphasized.Due to this fea` ture, when the suction stroke is started, the valvering 22 leaves its seat at once, in rey `sponseto the vacuum thuscreated, and uncgvers all of the apertures 20 substantiallysimultaneously. There can be no tilting of the rmg 22, with attendantdanger of wirev drawing of the air as it is suckedY in. Furthermore itis. possible to drive thepiston 12 up close to the cup 23, asV shown 1nFig.

v1, `and thus most eliciently to utilize the cylinder volume.,

In order to provide a proper support for the cup 25, as lwell as a stopto limit-. the opening movement of the valve 22, I prefer t'o interposea disc-like member 28 between the spring you 25 and the plate 18. Theedge of this disc extends over the valve 22, and thus prevents it fromopening too far. pertures 29 and 30 are provided in both the cup 25 anddisc 28 to leave the discharge passageways 21 unimpeded. Furthermoreanother series of apertures 31 may be provided in the spring cup 25 inorder to ensure against the "trapping of any air between the cup 25 andthe disc 28, as the cup 1s exed. and unfiexed in the course of itsoperation.

The .series of discharge apertures 21, which are adapted to connectthecylinder 11 with the discharge passageway 15, may be controlled by aspring pressed valve ring 32, on that side of thevalve plate 18 which isfarthest from the cylinder chamber. This valve ring 32, bein directlyexposed to the ynientary spring pressure on the valve ring 32. Acoiledspring 33 may be utilized for providing this weak pressure. A guide post34, fastened to the plate 18, as by aid of the bolt 27 before mentioned.provides a flange vabutment 35 for the stationary end of the spring.Furthermore a shoulder 36 on the post 34' serves as a stopl forpreventing the valve 32 from opening too far. The Spring 33 is adjustedso that it is just strong enough to keep the valve seated when there isequal pressure on both sides of the valve. ln this way, as soon assufficient preponderance of pressure exists in the cylinder'll, there isa certainty that the valve 32-will be lifted, and the discharge properlyaccomplished.

The mechanical arrangement of the' valves is of importance also. lAll oflthe valvey parts for both the intake and the discharge, are supportedona common member, such as the plate 18, and by loosening arelativelyfew bolts 19, theI entire .valve structure may easily` be removed,repaired, and replaced should occasion demand.

Due to the great centainty of action ofd 4both the intake and dischargevalves, their degree of efficiency which materiali exceeds that of othertypes. There is su stantally no dead ,volumel in the cylinder chamber,because of the extremely compact intake` valve arrangement, and thisfeature contributes materially to the desirable re-v sults which havebeen obtained.`

I claim L v 1. In a fluid compressor, a cylinder, a piston reciprocatingwithin the cylinder, a discharge valve structure, 4and an intake valvestructure, comprising a member at the cylinder end and yhaving dischargeapertures, a closure within the cylinder for all of the apertures, aflatspring having a cupped vedge engaging the closure, and

.means for fastening the spring near its center, whereby its edge may befree to urge the closure to close the apertures.

2. In a fluid compressor, a cylinderfa pisy tn reciprocating within thecylinder, a

l plate forming the end wall of the cylinder,

` piston reciprocating within the cylinder, a

said plate having a series of intake apertures, a common closure for allof the apertures, said closure being disposed 'within the cylinder,andmeans for urging the closure in a direction to keep the aperturesclosed, comprising a spring' resiliently engaging the closure on acontinuous surface which is substantially coextensive with the vseriesof intake apertures.

3. In a Huid compressor, a cylinder, a piston reciprocating within thecylinder, a

plate forming the end wall of the cylinder, said plate providing anannularly arranged intake for the piston, a ring-like closure for theintake disposed within the cylinder, and

a shallow cup spring urging the closure to' closed position, the springen aging the closure nearthe edge of the cosure, and fastened near itscenter to the plate.

4. In a fluid compressor, a cylinder, a

plate forming the end wall of the cylinder,

-said plate having a series of intake apertures annularly arranged, avalve closure of ring form for the. apertures, means for limiting theopening movementof the closure, anda cup spring urging the closure toclosed position, the edge of said cup engaging the ring closure near itsoutside edge along a substantially continuous'annular surface. y

5. A valve structure comprising a member having apertures, a commonclosure for all the apertures, a flat sprin having a cupped edgeengaging the c o sure, and means for fastening the spring near itscenter, whereby its edge may be free to urge the closure to close theapertures.Y

`6. In a valve structure, a member having a series of apertures, acommon lclosure for all of the apertures, and means for urging i.

vthe closure in a direction to keep Ythe apertures closed, comprising aspring resiliently engaging the closure on a continuous surfacev whichis substantially coex'tensive withthe series of intake apertures.

7. In a vvalve structure, a member pro-l viding an annularlyT arrangedvalve opening, a ring-like closure for the intake, and

a shallow cup spring urging the closure to closed position; the springengaging the closure near `the edge of the closure, and fastened nearits center to the member.

8. In a valve structure, a member having a series of Aaperturesannularly arranged,

a valve closure of ring form for the apertures, means for limiting theopening move-v ment of the closure, and a cup spring urging the closureto closed position, the edge of urge it to closed position, a guide postex-` tending from the wall and around which the closure is disposed, and'a `helical spring guided by said post for .urging the closure to closedposition, said spring exerting only a weak force against thel closure. v

10. Ina valve structure for a Huid compressor cylinder, a plate havingapair of series of annular apertures, said series `be ing concentric,ring shaped closures for both series, said closures being disposed onopposite sides of the plate, a, cup-like spring engaging one of the ringclosures, a guide ostaround which the other ring closure is disposed,means for fastening the guide post, plate, and cup spring together, anda helical spring guided'by the post and having its end turn engagingsai-d other ring closure. y

In testimony whereof, I have hereunto s et m hand. e

'y DEXTER C. BAKER.

